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Solid and Hazardous Wastes. In nature, there is essentially no wastes because the wastes of one organism become the nutrients for another. This recycling of nutrients is the basis for one of the scientific principles of sustainability .
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Solid and Hazardous Wastes In nature, there is essentially no wastes because the wastes of one organism become the nutrients for another. This recycling of nutrients is the basis for one of the scientific principles of sustainability. Humans produce large amounts of wastes that go unused and pollute the environment. Categories of wastes Solid waste: any unwanted or discarded material we produce that is not a liquid or gas. • Municipal solid waste (MSW): produce directly from homes and workplaces, containing a mix of paper, food, cans bottles etc. Referred to as trash or garbage. The top four contributors to MSW in order by weight are: Paper, yard waste, food waste, and plastics. • Industrial solid waste: produced by mines, agriculture and industries that supply people with goods and services. Ex: empty chemical containers, ash, tires and many of the things above.
Hazardous (toxic) waste: threatens human health or the environment because it is toxic, chemically active, corrosive or flammable. Ex: Industrial solvents, medical waste, car batteries, and pesticides. There are three categories: Hazardous or Toxic Waste • Organic compounds: Solvents, pesticides, and dioxins. • Toxic heavy metals: Lead, mercury, cadmium, Chromine and arsenic. Highly radioactive waste produced by nuclear power plants and weapons facilities must be stored safely for 10,00 to 240,000 years depending on the half-life of the material.
Why Reduce Solid and Hazards Wastes? According to the U.N. environmental Programme (UNEP) developed counties produce 80-90% of all hazardous waste. Currently the U.S. is the biggest contributor with China catching. Three fourths of the materials we dispose of represents an unnecessary waste of the Earth’s resources. We can recycle or reuse 90% of the produced MSW. Countries collect, mix and bury MSW in landfills. Once mixed they can mix with hazards wastes or become too expensive to recover and these resources are lost. Countries burn MSW which pollutes the air and leaves a toxic ash that must be buried. So called pollution prevention causes rich countries to move polluting industries to poor countries. Also making the products we use and then discard creates large amounts of air, water and land pollution. Solid wastes polluting a river in Jakarta, Indonesia. The man in the boat is looking for items to salvage or sell.
Waste in the United States The United States leads the world in producing solid waste. We produce about a third of the world’s solid waste with only 4.6% of the worlds population. and buries more than half of it in landfills. • About 98.5% is industrial solid waste. Mining (76%), Agriculture (13%) and industry (9.5%). • The remaining 1.5% is MSW. • About 54% of U.S. MSW is dumped into landfills, 25% is recycled, 7% is composted, and 14% is burned in incinerators. What do we throw away? 3,200 plastic shopping bags per second Tires (enough to circle the planet 3 times per year) Carpet (enough to cover Delaware per year) Diapers (reach the moon and back seven times) 2.5 billion plastic bottles per hour The U.S. also leads the way in trash per person at 4.5 pounds of MSW per day. Recycling is helping since 1990 the MSW per person has leveled off.
Electronics: Environmental Killers E-waste consists of toxic and hazardous waste such as PVC, lead, mercury, and cadmium. Your computer uses 700 or more materials obtained from mines, oil wells and chemical factories. For each pound of electronics 8000 pounds of solid and liquid waste is produced. Producing the chips produce 630 times its weight in solid and hazards waste. Extracting the resources and using them require large amounts of energy and burning fossil fuels emitting CO2 and other pollutants into the atmosphere. The U.S. produces almost half of the world's e-waste but only recycles about 10% of it.
Integrated Waste Management How should we deal with Solid waste? 1. Waste Management: The attempt to reduce the environmental impact of MSW without trying to reduce the amount of waste produced. The most common approach is to mix MSW and burying them, burning them or shipping to another location. 2. Waste reduction: Produce less waste and pollution. This includes the three R’s: reduce, reuse, and recycle. Scientists call for using a variety of strategies to deal with MSW and hazardous waste described as Integrated Waste Management with an emphasis on waste reduction.
Integrate Waste Management Raw materials Processing and manufacturing Products Solid and hazardous wastes generated during the manufacturing process Waste generated by households and businesses Remaining mixed waste Food/yard waste Hazardous waste Plastic Glass Metal Paper To manufacturers for reuse or for recycling Hazardous waste management Compost Incinerator Landfill Fertilizer Fig. 21-5, p. 565
We Can Cut Solid Wastes by Following the R’s Refuse: to buy items that we really don’t need. Reduce: consume less and live a simpler and less stressful life by practicing simplicity. Reuse: rely more on items that can be used over and over. Reusing products is an important way to reduce resource use, waste, and pollution in developed countries. • Reusing can be hazardous in developing countries for poor who scavenge in open dumps for items they can reuse or sell. They can be exposed to toxins or infectious diseases. Reusing items decreases the use of matter and energy resources and reduces pollution and natural capital degradation; recycling does so to a lesser degree. Repurpose: use something for another purpose instead of throwing it away. Recycle: paper, glass, cans, plastics…and buy items made from recycled materials.
Recycling Recycling: Conservation of resources by converting them into new products. Recycling reduces unsightly and environmentally harmful litter. Households and workplaces produce 5 major types of materials that can be recycled: Paper Glass Aluminum Steel Some plastics Materials can be recycled in two ways: Primary (closed loop) recycling: materials are turned into new products of the same type. Aluminum cans are turned into new aluminum cans. Secondary recycling: materials are converted into different products. • Used tires shredded and converted into rubberized road surface. • Newspapers transformed into cellulose insulation. • Types of wastes that can be recycled • Preconsumer: internal waste from the manufacturing process (3/4) • Postconsumer: external waste from consumer use of products (1/4)
Recycling Paper Recycling paper has a number of environmental (reduction in pollution and deforestation, less energy expenditure) and economic benefits and is easy to do. About 55% of trees are harvested to make paper. The internet was supposed to reduce paper use, however most people still print out their searches and there is no drop in per capita consumption in the United States. Recycling paper uses 64% less energy, 35% less water pollution and 74% less air pollution and no trees are cut down. Recycling in done by removing ink, glue, coating and converting it back to pulp. U.S. currently recycles 56% of its paper and paperboard. Despite this number the U.S. throws away more paper than is used in all of China. Denmark, recycles about 97% of its paper. Problems: Many U.S. mills are not able to process waste paper. Many countries like Mexico, import a large amount of wastepaper from the U.S. (19%). Bleaching paper with chlorine compounds (Cl02) is bad for the environment. Solution: Replacement of chlorine-based bleaching chemicals with H2O2 or O2
For example, the Sunday edition of the New York Times consumes 62,000 trees.
Recycling Glass and Aluminum Glass: U.S. recycles about 36% of its glass containers. It costs less to recycle glass than to make new glass. Mixed color glass is used for Glassphalt:a variety of asphalt that uses crushed glass. It has been used as an alternative to conventional bituminous asphalt pavement since the early 1970s. Glassphalt must be properly mixed and placed if it is to meet roadway pavement standards Aluminum is the most recycled material in the U.S. because of money gained by the recycler. Making a new can from an old one requires a fraction of the energy than to make a new can from raw materials (Aluminum ore). Approximately 2/3 of cans are recycled each year, saving 19 million barrels of oil annually.
Recycling Plastic Plastics: Large polymers or resins (organic compounds) made from oil and natural gas. Plastic containers are thrown into the environment and end up by roads, beaches and in water. They threaten seabirds, marine mammals, and sea turtles that can mistake a sandwich bag for a jellyfish or get caught in plastic nets. Currently only about 4% of plastic is recycled in the United States. Reasons plastic recycling is low Many plastic resins are hard to isolate because containers are made of many different resins. For example ketchup bottles are composed of six layers of resin. Recovering resins does not yield much material Cheaper to make new plastics than to recycle. The exception is PET.
Recycling PET and PVC PET (Polyethylene terephthalate) is used to make soft drink bottles, peanut butter jars, etc. PET can be recycled into fiberfill for sleeping bags, carpet fibers, rope, and pillows at a cost efficient rate. Most common recycled plastic. PVC (Polyvinyl chloride)is used in shampoo and cooking oil bottles & fast-food service items. Advantage: Replaced lead pipes for a lot of water services reducing lead compounds in water. Problems: If one PVC bottle is mixed in with the PET, recycling is useless. This is why there are markings on certain plastic bottles.
Recycling HDPE and LDPE HDPE (High-density polyethylene)is found in milk jugs, butter tubs, detergent bottles, and motor oil bottles. HDPE can be recycled into flowerpots, trashcans, traffic barrier cones, and detergent bottles. LDPE (Low-density polyethylene)is found in grocery bags, bread bags, shrink-wrap, and margarine tub tops. LDPE can be recycled into new grocery bags. Outlawing plastic grocery bags in some counties is aimed to reduce this waste.
Recycling PP and PS PP (Polypropylene) is used in yogurt containers, straws, pancake syrup bottles, and bottle caps. PP can be recycled into plastic lumber, car battery cases, and manhole steps. PS (Polystyrene) is found in disposable hot cups, packaging materials (peanuts), and meat trays. In 1941, Dow Chemical invented a Styrofoam process.PS can be recycled into plastic lumber, cassette tape boxes, and flowerpots.
Seven Strategies that Industries and Communities can use to Reduce Resource use, Waste and Pollution. • (1) Redesign manufacturing processes and products to use less material and energy. Plastic bottles and aluminum cans use less materials than before. • (2) Redesign manufacturing processes to produce less waste and pollution. Developing strategies in which waste from some businesses are raw materials for others. (3) Develop products that are easy to repair, reuse, remanufacture, compost, or recycle (4) Eliminate or reduce unnecessary packaging (5) Use fee-per-bag waste collection systems. Charge consumers for the amount of waste they throw away but provide free pick up for recyclable or reusable items. (6) Establish cradle-to grave responsibility laws. Require companies to take back consumer products such as electronic equipment, appliances and motor vehicles. (7) Restructure urban transportation systems. Rely more on mass transit and bikes than cars.
Burning Solid Waste One of 600 global Waste-to-energy incinerator with pollution controls that burns mixed solid wasteand turns it into steam that runs an electric producing generator. 98 in the United States which burned 16% of the nation’s solid waste and produces less CO2 emissions than power plants that run on fossil fuels.
Burying Solid Wastes: Landfills Solid waste is placed in a hole, compacted, and covered with soil. Covering it reduces the number of rats associated with solid waste, lessens the danger of fire, and decreases the odor. Open dumps are essentially holes in the ground where trash is dumped. They are rare in developed countries. • Sanitary landfills: solid wastes are spread out in thin layers, compacted and covered daily with a fresh layer of clay or plastic foam.
When landfill is full, layers of soil and clay seal in trash Topsoil Electricity generator building Sand Clay Methane storage and compressor building Leachate treatment system Garbage Probes to detect methane leaks Pipes collect explosive methane as used as fuel to generate electricity Methane gas recovery well Leachate storage tank Compacted solid waste Groundwater monitoring well Garbage Leachate pipes Leachate pumped up to storage tank for safe disposal Sand Synthetic liner Leachate monitoring well Sand Groundwater Clay and plastic lining to prevent leaks; pipes collect leachate from bottom of landfill Clay Subsoil Fig. 22-12, p. 532
Landfills: Current Criteria Compacted clay and plastic sheets are at the bottom (prevents liquid waste from seeping into groundwater) Currently landfills are the primary method of waste disposal in the United States, with 54% ending up there. A double liner system must be present (plastic, clay, plastic, clay), and a system to collect leachate (liquid that seeps through the solid waste) Oil, Air Conditioner Coolants, Lead Acid (Car Batteries) and Antifreeze: Not allowed. Must go to an automotive or environmental company for recycling. Tires: Are usually allowed if they are quartered or shredded. According to the EPA, all landfills eventually leak, passing the effects of contamination and cleanup costs on to future generations. Leachate is the most serious problem associated with sanitary landfills.
Detoxifying Hazardous Wastes Detoxifying hazardous wastes involves converting them into less hazardous wastes. Physical Methods: using charcoal or resins to separate out harmful chemicals. Deadly wastes can be encapsulated in glass or cement and put in secure storage sites. Chemical Methods: using chemical reactions that can convert hazardous chemicals to less harmful or harmless chemicals. • Bioremediation: bacteria or enzymes help destroy toxic and hazardous waste or convert them to more benign substances. • Phytoremediation: involves using natural or genetically engineered plants to absorb, filter and remove contaminants from polluted soil and water. Incineration: heating many types of hazardous waste to high temperatures – up to 2000 °C – in an incinerator can break them down and convert them to less harmful or harmless chemicals. Plasma Arc Torch: passing electrical current through gas to generate an electric arc and very high temperatures can create plasma.
Radioactive contaminants Organic contaminants Inorganic metal contaminants Poplar tree Brake fern Sunflower Willow tree Indian mustard Landfill Polluted groundwater in Oil spill Polluted leachate Soil Decontaminated water out Soil Groundwater Groundwater Phytoextraction Roots of plants such as Indian mustard and brake ferns can absorb toxic metals such as lead, arsenic, and others and store them in their leaves. Plants can then be recycled or harvested and incinerated. Phytodegradation Plants such as poplars can absorb toxic organic chemicals and break them down into less harmful compounds which they store or release slowly into the air. Rhizofiltration Roots of plants such as sunflowers with dangling roots on ponds or in green- houses can absorb pollutants such as radioactive strontium-90 and cesium-137 and various organic chemicals. Phytostabilization Plants such as willow trees and poplars can absorb chemicals and keep them from reaching groundwater or nearby surface water.
Long-Term Storage of Hazardous Waste Ideally, burial on land or long-term storage of hazardous and toxic wastes should be used only as a third resort after phytoremediation and plasma torch arc. Currently burial on land is the most widely used method in the U.S. Hazardous waste can be disposed of on or underneath the earth’s surface, but without proper design and care this can pollute the air and water. • Deep-well disposal: liquid hazardous wastes are pumped under pressure into dry porous rock far beneath aquifers. 64% of all liquid hazardous wastes in the U.S. are disposed of this way.
Surface impoundments: excavated depressions such as ponds, pits, or lagoons into which liners are placed and liquid hazardous wastes are stored. The EPA found that 70% of these storage basins in the U.S. have no liners, and up to 90% of them may threaten groundwater. Eventually all liners will leak.
Long-Term Retrievable Storage: Metal drums are used to stored them in areas that can be inspected and retrieved. This is designed for materials like mercury which cannot be destroyed, detoxified or safely buried. Secure hazardous waste landfills: Sometimes hazardous waste are put into drums and buried in carefully designed and monitored sites. In the U.S. there are only 23 commercial hazardous waste landfills.
Mercury Mercury is among a group of pollutants called persistent bioaccumulative toxins or PBTs. These pollutants "persist" in the environment, meaning that they do not break down or go away. Mercury cannot be destroyed, it cannot be combusted, and it does not degrade. Mercury also "bioacccumulates" in the environment, meaning it builds up in the food chain over time. Mercury can be released in the environment from natural sources, such as volcanic and geothermal activity, marine environments or forest fires, or it can be released from anthropogenic (man-made) sources like coal-fired power plants and other industrial activities. Recent studies suggest that human activity contributes 50-70% of the mercury in the environment globally. Once mercury enters the environment, it circulates in and out of the atmosphere until it ends up in the bottoms of lakes and oceans.
Hazardous Waste Regulations in the United States Two major federal laws regulate the management and disposal of hazardous waste in the U.S. The Resource Conservation and Recovery Act (RCRA) pronounced RICK-ra, enacted in 1976, is the principal federal law in the United States governing the disposal of solid waste and hazardous waste Goals of RCRA: 1. Protecting human health and the natural environment from the potential hazards of waste disposal. 2. Energy conservation and natural resources. 3. Reducing the amount of waste generated, through source reduction and recycling 4. Ensuring the management of waste in an environmentally sound manner.[2] It is now most widely known for the regulations promulgated under RCRA that set standards for the treatment, storage and disposal of hazardous waste in the United States. Cradle-to-the-grave system to keep track waste.
Superfund is the common name for the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA), a United States federal law designed to clean up sites contaminated with hazardous substances The Superfund law was designed to have polluters pay for cleaning up abandoned hazardous waste sites. • Only 70% of the cleanup costs have come from the polluters, the rest comes from a trust fund financed until 1995 by taxes on chemical raw materials and oil. Pace of cleanup has slowed Superfund is broke Leaking Barrels of Toxic Waste at a Superfund Site in the United States
Core Case Study: Love Canal — There Is No “Away” Between 1842-1953, Hooker Chemical sealed multiple chemical wastes into steel drums and dumped them into an old canal excavation (Love Canal). In 1953, the canal was filled and sold to Niagara Falls school board for $1. The company inserted a disclaimer denying liability for the wastes. In 1957, Hooker Chemical warned the school not to disturb the site because of the toxic waste. • In 1959 an elementary school, playing fields and homes were built disrupting the clay cap covering the wastes. • In 1976, residents complained of chemical smells and chemical burns from the site. High number of birth defects were recorded fro the area.
President Jimmy Carter declared Love Canal a federal disaster area. The area was abandoned in 1980. It still is a controversy as to how much the chemicals at Love Canal injured or caused disease to the residents. Love Canal sparked creation of the Superfund law, which forced polluters to pay for cleaning up abandoned toxic waste dumps. Assignment: Describe the following in your notes: Read section 21-6: know NIMBY, NIABY, NOPE, Environmental justice, Basel Convention, POPs, The Dirty Dozen, Swedish Parliament, and Transitioning to a Low-Waste Society.